A kaleidoscope of parties in India's Parliament

India is a kaleidoscope of seven national political parties and 31 regional ones. Few have an impact in Parliament besides the Congress Party of the Nehru-Gandhi house. In all, there are 544 seats in the Lok Sabha, the lower house of Parliament. Those not accounted for below are either held by independents or other small parties, or are vacant. Two members are nominated by the ruling party.

Congress (I) Party, led by Prime Minister Rajiv Gandhi, is India's ruling party. (''I'' stands for Indira.) It is the country's only truly national party, with strongholds among all religions, regions, and castes. But since Indira Gandhi's rise to power in 1966, urban intellectuals, professionals, and academics have slowly been abandoning it. An outgrowth of the grand old Indian National Congress that waged India's struggle for independence, the Congress Party has ruled the nation for 35 of its 37 independent years. The Congress (I) emerged from a three-way Congress Party split in January 1978. Seats: 339.

Bharatiya Janata Party (Indian People's Party), headed by Atal Behari Vajpayee, is a party of Hindu nationalism. It was formed in April 1980 as a breakaway faction from the Janata Party, following its defeat in the 1980 polls. Its strength lies in the six states of the northern Hindi belt and in New Delhi, though it has pockets of support in Maharashtra and Karnataka. Seats: 16.

Communist Party of India (CPI), led by C. Rajeswara Rao, is pro-Moscow and often supported by the Congress (I) in parliamentary votes. Its strongholds are in Kerala, Tripura, and West Bengal, though its strength in all three states is not as significant as that of its rival, the Communist Party of India (Marxist). Its strongest appeal is mainly among urban workers and technocrats. Seats: 13.

Communist Party of India (Marxist), more independent and more popular than the CPI, controls state governments in Tripura and West Bengal. A prominent member, West Bengal's chief minister, Jyoti Basu, has been a leading proponent of opposition unity. The party's constituency is essentially the same as that of the CPI, though it has more academics and intellectuals. Seats: 36.

Telugu Desam, organized in 1982, is the ruling party of Andhra Pradesh. Its charismatic chief minister, the former film idol N. T. Rama Rao, was toppled by the central government in August and returned to power a month later in a blaze of national publicity. The party will contest 34 of Andhra's 42 parliamentary seats and is a hands-down favorite to capture a solid majority. Seats: none.

Dalit Mazdoor Kisan Party (Party of the Lower Caste and Untouchable Hindus, Farmers, and Farm Laborers) was formed in October as an alliance of three parties. Its leader is Charan Singh, president of the Lok Dal Party and Indian prime minister from July 1979 to January 1980. The Democratic Socialist Party and the Rashtriya Congress complete the trio, whose appeal is in the Hindi belt. Combined seats: 31 (Lok Dal 23, Democratic Socialist Party 8).

Janata Party is a coalition formed in early 1977 by a group of opposition politicians, most of whom had been jailed during Mrs. Gandhi's June 1975-March 1977 period of ''emergency'' rule. The coalition of five parties, including the Lok Dal and members of the present Bharatiya Janata Party, swept to victory in the March 1977 election almost exclusively on an anti-Indira Gandhi platform. Its power base was the northern Hindi belt. By August 1979, however, the coalition had fallen apart and it lost power in January 1980. Chandra Shekhar leads the old coalition, which heads a minority government in Karnataka. The party is contesting the elections at the head of a loose coalition of six parties, called the United Front. Seats: 21.

Congress Party (Socialist) is a breakaway group from the Congress Party. When its leader died in 1980, it changed its name from Congress (U) Party to Congress (S) Party. Although the ''S'' stands for ''Socialist,'' most people had assumed it stood for the name of the party's new president, Sharad Pawar, a former chief minister of Maharashtra State. The fact that the party has renamed itself three times since 1978 is testament to the importance in Indian politics of a party leader's name. Seats: 5.

Rashtriya Sanjay Manch (National Sanjay Platform) was formed in March 1983 by Maneka Gandhi, widow of the prime minister's late brother, Sanjay. The party hopes to attract the votes of women, Muslims, and youth, and is campaigning hardest in the crucial northern state of Uttar Pradesh. With 85 seats in Parliament, Uttar Pradesh has the largest representation of any Indian state. Seats: 3.

National Conference is the dominant party of Jammu and Kashmir, the only state with a Muslim chief minister. Its leader, Farooq Abdullah, was toppled as chief minister by the central government in July. Dr. Farooq is concentrating on campaigning nationally in an effort to rally the country's Muslims votes behind the opposition parties. Though they form only 11.24 percent of the Indian population, Muslims tilt the scales for at least 75 of Parliament's 542 seats because of their concentration. In the past, Muslims have voted traditionally for the Congress Party, awarding the odd seat here and there to small Muslim parties. Seats: 3.

All India Anna Dravida Munnetra Kazhagam (All India Dravidian Forward Party), led by former film idol M. G. Ramachandran, is the ruling party in Tamil Nadu. Having formed an electoral alliance with the ruling Congress (I), it is unlikely to make any significant opposition gains beyond the 14 of the state's 39 parliamentary seats now held by Tamil Nadu's opposition party, the Dravida Munnetra Kazhagam. Seats: 3.